THERMAL STUDIES OF METAL-FILMS PREPARED WITH OXYGENATED SOLVENTS .12.

Citation
G. Cardenas et al., THERMAL STUDIES OF METAL-FILMS PREPARED WITH OXYGENATED SOLVENTS .12., Boletin de la Sociedad Chilena de Quimica, 39(3), 1994, pp. 199-204
Citations number
13
Categorie Soggetti
Chemistry
ISSN journal
03661644
Volume
39
Issue
3
Year of publication
1994
Pages
199 - 204
Database
ISI
SICI code
0366-1644(1994)39:3<199:TSOMPW>2.0.ZU;2-K
Abstract
Copper, silver and gold colloids have been prepared by Chemical Liquid Deposition (CLD) with dimethoxymethane, 2-methoxyethyl ether and ethy lenglycol dimethyl ether. The metals are evaporated to yield atoms whi ch are solvated at low temperatures and during the warm up process col loidal sols with metal clusters are obtained. Evaporation of the solve nt was carried out under vacuum generating metal films. These films ar e showing very low carbon/hydrogen content and were characterized by e lemental analyses and infrared spectroscopy. The thermal stabilities o f these metal films have been studied by thermogravimetry (TG) between 25 and 550-degrees-C under nitrogen flow. The decomposition temperatu re was obtained from the maximum of the first derivative from TG curve . The kinetic parameters of the thermal decomposition were determined by the Arrhenius equation. All these films degrade in a single step. T he kinetic data thus obtained show that the thermostabilities decrease in the order: Au-DMM > Au-EDE > Cu-DMM > Cu-EDE > Ag-EDE > Ag-DMM > A u-2-MEE > Ag-2-MEE > Cu-2-MEE. The thermal stability seems to depend o n the metal and on the size of the ligand. The decomposition reaction order is zero for Au, Ag-DMM and Au-EDE. However, n = -0.25 was obtain ed for the other films. This means that we are in the presence of a mu ltistep decomposition mechanism. The pre-exponential factor, the react ion order, the decomposition temperature and the activation energy of the decomposition reaction for Ag, Au and Cu films have been determine d.